einstein

“If I have seen further than others, it is by standing upon the shoulders of giants.” This famous quote by Isaac Newton points to an axiom that lies at the heart of The Sciences — knowledge precedes knowledge.

What we know today is entirely based upon what we learned in the past. This general pattern is echoed throughout recorded history by the revelation of one scientific mystery leading to other mysteries… other more compounding questions. In the vast majority of cases these mysteries and other questions are sprung from the source of an experiment with an unexpected outcome sparking the question: “why the hell did it do that?” This leads to more experiments which creates even more questions and next thing you know we go from moving around on horse-drawn carriages to landing drones on Mars in a few generations.

The observant of you will have noticed that I preceded a statement above with “the vast majority of cases.” Apart from particle physics, almost all scientific discovery throughout recorded history has been made via experiment and observation. There are a few, however, that have been discovered hidden within the confines of an equation, only later to be confirmed with observation. One such discovery is the Black Hole, and how it was stumbled upon on a dusty chalkboard in the early 1900s will be the focal point of today’s article.

When you hear someone say “Einstein”, what’s the first thing that pops into your head? Is it high IQ… genius… or maybe E=MC2? Do you picture his wild grey hair shooting in all directions as he peacefully folds the pages back from his favorite book? You might even think of nuclear bombs, clocks and the Nobel Prize. It will come as a surprise to many that these accomplishments were a very small part of his life. Indeed, Einstein turned the world of classical physics upside down with his general theory of relativity. But he was only in his early twenties when he did so.

What about the rest of his life? Was Einstein a “one-hit-wonder”? What else did he put his remarkable mind to? Surely he tackled other dilemmas that plagued the scientific world during his moment in history. He was a genius after all… arguably one of the smartest people to have ever walked the earth. His very name has become synonymous with genius. He pulled the rug out from under Isaac Newton, whose theories had held the universe together for over 300 years. He talked about enigmatic concepts like space and time with an elegance that laid bare the beauty hidden within their simplicity. Statues have been made of him. His name and face are recognizable across the globe.

But when you hear someone say “Einstein”, do you think of a man who spent the better half of his life… being wrong? You should.

The story of Schrodinger’s cat is well known, and one of quantum theory’s most popular phrases on the world stage. You can find his cat on t-shirts, bumper stickers, internet memes and the like. However, few know the origins of the cat, and how it came into being. I suspect many do not understand it beyond the “dead and alive at the same time” catchphrase as well. Not surprisingly, it was Einstein who was at the center of the idea behind Schrodinger’s cat. In a vibrant discussion between the two via letters across the Atlantic, Schrodinger echoed Einstein’s concerns with the following:

Contained in a steel chamber is a Geiger counter prepared with a tiny amount of uranium, so small that in the next hour it is just as probable to expect one atomic decay as none. An amplified relay provides that the first atomic decay shatters a small bottle of prussic acid. This and -cruelly- a cat is also trapped in the steel chamber. According to the wave function for the total system, after an hour, sit venia verbo [pardon my language], the living and dead cat are smeared out in equal measure.

This was the first mention of Schrodinger’s cat, and one would not be incorrect in stating that this paragraph from a letter was where the cat was born. However, the original idea behind the thought experiment was from Einstein and his loathing of the wording of the Einstein-Podolsky-Rosen (EPR) paper. He expressed his frustrations with Schrodinger with a few simple examples, who then catapulted it into his famous paradox . In this article we’re going to explore not so much the cat, but the meaning behind the thought experiment and what it is meant to convey, while keeping it simple enough for anyone to understand. So next time you see it on a t-shirt, you will be able to articulate the true meaning and know the real Schrodinger’s cat.

Richard Feynmann noted more than once that complementarity is the central mystery that lies at the heart of quantum theory. Complementarity rules the world of the very small… the quantum world, and surmises that particles and waves are indistinguishable from one other. That they are one and the same. That it is nonsensical to think of something, or even try to visualize that something as an individual “particle” or a “wave.” That the particle/wave/whatever-you-want-to-call-it is in this sort of superposition, where it is neither particle nor wave. It is only the act of trying to measure what it is that disengages the cloaking device and the particle or wave nature is revealed. Look for a particle, and you’ll find a particle. Look for a wave instead, and instead you’ll find a wave.

Complementarity arises from the limits placed on measuring things in the quantum world with classical measuring devices. It turns out that when you try to measure things that are really really really small, some issues come up… some fundamental issues. For instance, you can’t really know exactly where a sub-atomic particle is located in space. You can only know where it is within a certain probability, and this probability is distributed through space in the form of a wave. Understanding uncertainty in measurement is key to avoiding the disbelief that hits you when thinking about complementarity.

This article is a continuation of the one linked above. I shall pick up where I left off, in that everyone agrees that measurement on the quantum scale presents some big problems. However, not everyone agrees what these problems mean. Some, such as Albert Einstein, say that just because something cannot be measured doesn’t mean it’s not there. Others, including most mainstream physicists, say the opposite — that if something cannot be measured, it for all practical purposes is not there. We shall continue on our journey by using modern technology to peer into the murky world of complementarity. But first, a quick review.

It was the year of 1687 when Isaac Newton published “The Principia“, which revealed the first mathematical description of gravity. Newton’s laws of motion along with his description of gravity laid before the world a revolutionary concept that could be used to describe everything from the motions of heavenly bodies to a falling apple. Newton would remain the unequivocal king of gravity for the next several hundred years. But that would all change at the dawn of the 20th century when a young man working at a Swiss patent office began to ask some profound questions. Einstein had come to the conclusion that Newtonian physics was not adequate to describe the findings of the emerging electromagnetic field theories. In 1905, he published a paper entitled “On the Electrodynamics of Moving Bodies” which corrects Newton’s laws so they work when describing the motions of objects near the speed of light. This new description became known as Special Relativity.

It was ‘Special’ because it didn’t deal with gravity or acceleration. It would take Einstein another 10 years to work these two concepts into his relativity theory. He called it General Relativity – an understanding of which is necessary to fully grasp the significance of gravitational waves.

One can be reasonably certain that when the title of an article includes the phrase “The Nature of Reality”, thought provoking words must surely lie ahead. But when that same title seems to inquire about a gentleman’s socks, coupled with an image of said gentleman’s socks which happen to be mismatched and reflect very loud colors , one might be moved in a direction which suggests the article is not of a serious nature. Perhaps even some sort of parody.

It is my hope that you will be pleasantly surprised with the subtle genius of Irish physicist [John Bell] and his use of socks, washing machines, and a little math to show how we can test one of quantum physic’s most fundamental properties. A property that does indeed reside in the very nature of the reality we are a part of. Few people can say they understand the Bell Inequality down to its most fundamental level. Give me a little of your time, and you will be counted among these few.

The philosopher in the street, who has not suffered a course in quantum mechanics, is quite unimpressed by the [Einstein-Podolsky-Rosen] correlations. He can point to many examples of similar correlations in everyday life. The case of Bertlmann’s socks is often cited. Dr. Bertlmann likes to wear two socks of different colours. Which colour he will have on a given foot on a given day is quite unpredictable. But when you see that the first sock is pink you can be already sure that the second sock will not be pink. Observation of the first, and experience with Bertlmann, gives the immediate information about the second. There is no accounting for tastes, but apart from that there is no mystery here. And is this [Einstein-Podolsky-Rosen] business just the same?

John Bell began his now famous paper with the above paragraph. The Bell Inequality started off like so many other great theories in science – as a simple thought experiment. Its conclusions were not so simple, however, and would lead the way to the end of Einstein’s idea of local hidden variables, and along with it his hopes for a deterministic universe. In this article, we’re going to look at the Bell inequality in great detail. Our guide will be a chapter from Jim Baggots’ The Quantum Story, as it has one of the best descriptions of Bell’s theory I’ve ever read.